Rigid Body Sim
Simulate points, geometry, or shapes as a dynamic, kinematic, or static rigid body.
What it does
Configures how a piece of geometry behaves once physics is turned on: falling and colliding as a solid object (Dynamic), moving along a scripted path while still pushing other things out of the way (Kinematic), or sitting immovable as something everything else bounces off (Static). Points, Geometry, analytic shapes and generic Shapes are all accepted.
This node does not run the simulation. Settings are stamped onto the geometry, which passes straight through. Wire its output into Physics World's entities input; that node owns the solve, each frame, on the GPU.
When to use it
An object that falls, tumbles and collides: Body Type set to Dynamic
A platform or door moving on a fixed path and shoving other objects: Kinematic
An unmovable floor, wall or obstacle for other bodies to collide with, in place of a plain Physics Collider: Static
Tuning how a body feels on impact: Friction, Restitution (bounciness), Mass, or the Solver's Iterations and Damping
| Parameter | Type | Default | What it does |
|---|---|---|---|
input | Any | — | Geometry to simulate as a rigid body (Points, Geometry, CRC primitives, or Shapes) |
body_type | String | "Dynamic" | Dynamic = affected by forces; Kinematic = scripted motion; Static = immovable collider. One of: Dynamic, Kinematic, Static. |
collider_shape | String | "Mesh" | Collision shape: Mesh (exact), Convex Hull, Box (AABB), Sphere (bounding). CRC inputs auto-detect as analytic SDF colliders. One of: Mesh, Convex Hull, Box, Sphere. |
mass | Number | 5 | Mass in kg (ignored for Static bodies) |
friction | Number | 0.500 | Surface friction (0 = frictionless, 1 = maximum) |
restitution | Number | 0.300 | Bounciness (0 = no bounce, 1 = perfect bounce) |
iterations | Number | 10 | Solver iterations per frame (higher = more accurate) |
damping | Number | 0.010 | Velocity damping (0 = none, 1 = full) |
strength | Number | 1 | Effect strength / wet-dry (0 = no effect, 1 = full). Editable, wirable, keyframable. |
Gotchas
Mass is ignored for Static bodies.
This node only tags the geometry with its physics settings. Nothing moves until the geometry reaches a Physics World node. If an object is not reacting, check that it is wired into Physics World's entities input.
Analytic-shape inputs, for instance a Distance Field sphere, are auto-detected and collided against their exact surface with no approximation, so no Collider Shape needs picking. The dropdown's Mesh / Convex Hull / Box / Sphere choices apply to ordinary mesh geometry.
Worked example
Add a Rigid Body Sim and wire the geometry into its input.
Set Body Type to Dynamic for a falling object, or Static for a floor or wall it should collide against.
Pick a Collider Shape. Box and Sphere are cheap for simple forms; Mesh is exact but pricier.
Adjust Friction and Restitution to taste, then wire the output into a Physics World node's entities input to see it simulate.
See also
Physics World · Physics Joint · Soft Body Sim · Geometry (meshes)